Register to reply

Calculating the Optical Rotation Value

by Interception
Tags: optical, rotation
Share this thread:
Interception
#1
Nov29-12, 06:03 PM
P: 15
1. The problem statement, all variables and given/known data So the problem states that we have a (+) enantiomer of a coumpund with an optical rotation of 50*. If a pure sample containes 42% of the (+) enantiomer and 58% of the (-) enantioimer, what is the optical rotation value. (By * i mean degrees)



2. Relevant equations I'm not sure which equation would apply to this situation. It's a small school, and our proffesor hardly went over this subject. We'd done a few problems, but none where like this.



3. The attempt at a solution I know that it will be a negative value since the the (-) enantiomer outnumbers the (+). I didn't know how to approach the problem, so I took 58%-the 42% to see how much of the (-) will contribute to the rotations since the 42% of the (+) enantiomer will counteract 42% of the (-) enantiomer. I got -16. I took this mean that 16% of the (-) enantiomer would be optically active, and 16% of 50 is 8, or in this case -8* of optical rotation. The negative value makes sense, and the fact that it's not a large number. Does this look right?
Phys.Org News Partner Science news on Phys.org
Flapping baby birds give clues to origin of flight
Prions can trigger 'stuck' wine fermentations, researchers find
Socially-assistive robots help kids with autism learn by providing personalized prompts
Borek
#2
Nov30-12, 01:53 AM
Admin
Borek's Avatar
P: 23,577
Looks OK to me.


Register to reply

Related Discussions
Large optical image rotation for project General Engineering 3
Calculating axis of rotation Differential Geometry 16
Calculating angle of a rotation for a line General Math 3
Calculating optical power output Engineering, Comp Sci, & Technology Homework 4
Calculating the Speed of the Earth's Rotation. Precalculus Mathematics Homework 5